1. Field of the Invention
The invention relates to load hauling machines and, more particularly, relates to a "power buggy," i.e., a relatively small, self-propelled load hauling vehicle having a storage bucket and operator's controls. The invention additionally relates to a power buggy designed to maximize operator safety, stability, and comfort.
2. Discussion of the Related Art
Power buggies are well-known light industrial vehicles designed to haul loads of from a few hundred pounds to a few tons. The typical power buggy comprises 1) a chassis supported on the ground via a plurality of wheels, 2) a storage bucket or dumping platform supported on the front end of the chassis and liftable to dump loads, and 3) a power source for propelling the vehicle and for operating other powered equipment on the vehicle. The typical power buggy is controlled by an operator who is stationed behind the power buggy and who either walks behind the power buggy or stands on an operator's platform mounted on the rear end of the chassis. Controls for the typical power buggy include a steering control mechanism, a speed control mechanism, an engine kill switch or similar controller, and dump controls which raise and lower the bucket. The vehicle is steered by a generally Y-shaped handlebar having a pair of handgrips. Vehicle propulsion is controlled by a squeeze lever mounted adjacent one of the handgrips. Power buggies of this general type are available from Miller, the Morrison Division of Amida Industries, Inc., the Whiteman Division of Amida Industries, Inc., and Schroeder Industries.
The typical power buggy has several disadvantages impairing operator comfort and even risking operator injury.
For instance, the controls of the typical power buggy are inconveniently located and/or difficult to operate. As an example, the squeeze lever used for speed control operates on generally the same principal as a motorcycle hand brake to the extent that the operator must simultaneously grasp the handgrip and pull a spring-loaded lever towards the handgrip. The vehicle is propelled at a speed proportional to the amount of force applied to the squeeze lever. The squeezing action is somewhat difficult for the operator, and prolonged operation of the squeeze lever can result in operator hand fatigue.
Directional control, i.e., shifting between forward and reverse, is effected by way of a separate shift control lever located remote from the squeeze lever. The operator must release one of the handgrips to shift between forward and reverse with resultant risk of loss of vehicle control. This risk is heightened by the fact that, because speed control and directional control are independent, it is possible for an operator to shift the vehicle while still applying force to the squeeze lever so that the vehicle reverses its direction of travel abruptly, thereby potentially causing the operator to lose his/her balance.
These problems are exacerbated by the fact that other controls are similarly relatively inaccessible and/or hard to operate. For instance, dump controls typically take the form of hand-operated levers which are spaced a substantial distance from the handgrips and which therefore require the release of one of the handgrips for their operation. Some power buggies attempt to alleviate this problem by supplementing the hand levers with redundant foot levers. However, operating the foot levers requires the shifting of the operator's weight to one foot with risk of loss of balance.
All of these factors conspire to render the power buggy relatively difficult to operate with risk of loss of vehicle control and even operator injury. At the very least, the operator risks substantial discomfort in operating the machine.
Many power buggies are powered either directly or indirectly by an internal combustion engine which is located at the rear end of the vehicle in close proximity to the operator. The typical power buggy lacks any effective device for isolating the operator from the engine. Operators of these power buggies therefore experience additional discomfort from the substantial noise, heat, and vibrations from the engine. The fuel tank certainly does nothing to alleviate this problem. In fact, the fuel tank typically comprises a metal tank located in front of the engine and having a relatively low capacity of no more than 1-2 gallons. This relatively small fuel tank must be refilled frequently, which requires on-site storage of fuel with consequent risk of spills.
Some power buggies have an operator's platform which extends rearwardly from the chassis and which permits the operator to stand on the platform and ride on the power buggy while operating it. Some of these platforms are movable from a raised, stowed position in which the platform extends generally vertically to a lowered, operative position in which the platform extends generally horizontally. In addition to reducing the length of the machine for transport, selectively stowing the operator's platform permits the operator to operate the power buggy by walking along behind it rather than riding on the platform. Walk-along operation may be a matter of preference to some operators and is actually quite desirable when the power buggy is being operated on soft ground or under other conditions in which the added weight of the operator could cause the vehicle to leave undesired tracks.
The typical operator's platform is not lockable in either its stowed position or its operative position. It instead relies on gravity to hold it in its operative position and relies on a spring mechanism or an over-center arrangement or the like to hold the platform in its stowed position. This lack of locking capability may risk operator injury under some circumstances. For instance, when the vehicle is traveling up a steep hill with the platform in its stowed position, the force of gravity may overcome the spring arrangement or over-center arrangement and cause the platform to fall backwardly on its own accord and injure the operator's legs. Conversely, if an operator backs into an obstruction while riding on the platform while it is in its operative position, that obstruction may force the platform upwardly and throw the operator from the vehicle or pinch the operator's feet between the platform and the chassis.
The need therefore has arisen to provide a power buggy that can be operated easily, safely, and comfortably while at the same time maximizing vehicle stability.